Tilarán Highlands (20406)
Costa Rica, Central America
Site overview
KBA status: confirmed
Global KBA criteria: A1a, A1e, B1, B2
Year of last assessment: 2024
National site name: Tierras altas de Tilarán
Central coordinates: Latitude: 10.7152, Longitude: -85.0902
System: terrestrial
Elevation (m): 50 to 2020
Area of KBA (km2): 1765.81716
Protected area coverage (%): 45.31
KBA classification: Global
Legacy site: Yes
Site details
Site description: This area includes most of the middle and upper zones above 500 m of the Cordillera Volcánica de Guanacaste. This mountain range is made up of volcanic massifs relatively isolated from each other by mountain passes that occur at an approximate elevation of 500 m (Bergoeing 1998). The elevation of these massifs ranges between 1,437 m (Volcán Orosí) and 2,020 m (Volcán Miravalles) and their geographical orientation means that the western slope of these volcanoes has a highly seasonal climate like the one that prevails in the northwest of the country ( Gomez 1986). The humid, seasonal and rainy climate, typical of the Caribbean side of the country, is the one that predominates on the eastern side of these volcanoes. These climatic differences make the vegetation and therefore the avifauna associated with it very different between both slopes. In the lowlands on the Pacific side of these volcanoes, the forest is mainly composed of tropical dry forest species (eg Guazuma ulmifolia, Enterolobium ciclocarpum and Samanea saman). When ascending to medium elevations, the humidity is greater and the dry season is shorter, so a large part of the trees and shrubs are evergreen, characteristic of Premontane and Montane Forests. Near the top there is a narrow strip with vegetation typical of the High Montane Forest with trees from the families Lauraceae, Mirtaceae, Fagaceae and Podocarpaceae. The undergrowth is dense and humid, dominated by species of the families Piperaceae, Rubiaceae and Melastomataceae and a palm of the genus Geonoma (Arecaceae). The top of the inactive volcanoes is covered by Elfin Forest, this forest is a vegetal-climatic association very different from the adjacent forests. Plant species that are found at the highest elevations of the Talamanca and Central Volcanic mountain ranges, such as Schefflera sp. and Clusia sp. Most of the tree species do not exceed 6 m and their trunks and branches are covered with mosses, bryophytes and other epiphytes. The undergrowth is extremely dense, dominated by species from the families Ericaceae, Rubiaceae, and Myrcinaceae. On the Caribbean slope, the transition between forests is much more gradual and it is not until near the top of the volcanoes that a drastic change in the type of vegetation is noticed. In all the volcanoes there are large extensions of abandoned pastures, covered mainly by grasses and shrubby vegetation. This type of environment is the result of livestock exploitation, and recurrent fires that occurred and continue to occur in that area of the country.
Rationale for qualifying as KBA: This site contains the entire known population of the threatened amphibians Craugastor andi (A1e), Incilius guanacaste (A1e), and Tlalocohyla celeste (A1a/A1e/B1). An additional 21 species of birds meet the thresholds for at least one criterion described in the Global Standard for the Identification of KBAs.
Additional biodiversity: Chamaepetes unicolor Crax rubra Odontophorus leucolaemus Electron carinatum Panterpe insignis Elvira cupreiceps Calliphlox bryantae Zentrygon costaricensis Zentrygon chiriquensis Aphanotriccus capitalis Cephalopterus glabricollis Dysithamnus striaticeps Margarornis rubiginosus Thripadectes rufobrunneus Scytalopus argentifrons Phainoptila melanoxantha Zeledonia coronata Chrysothlypis chrysomelas Bangsia arcaei Chlorophonia callophrys Diglossa plumbea Zentrygon lawrencii Lampornis calolaemus Trogon collaris
Manageability of the site: At present, 28% of this site falls is managed under Costa Rica's protected area network.
Other site values: At present, 28% of this site falls is managed under Costa Rica's protected area network.
Delineation rationale: This site was delineated as an IBA in 2007. A more precise delineation rationale is not available.
Habitats
| IUCN Habitat | Coverage % | Habitat detail |
|---|---|---|
| Forest |
Threats
| Threat level 1 | Threat level 2 | Threat level 3 | Timing |
|---|---|---|---|
| Climate change & severe weather | Other impacts | Ongoing | |
| Climate change & severe weather | Habitat shifting & alteration | Ongoing | |
| Invasive & other problematic species, genes & diseases | Invasive non-native/alien species/diseases | Named species | Ongoing |
| Climate change & severe weather | Droughts | Ongoing |
Additional information
Contributors: Esteban Brenes-Mora (ebrenes@rewild.org)